1. Field of the Invention
The invention relates to vacuum cleaners and, more particularly, to vacuum cleaners having an agitation brush. In one of its aspects, the invention relates to a vacuum cleaner having cutters positioned adjacent the brush and any brush drive belt to prevent build-up of elongate particles, such as hair and thread, that will interfere with operation of the brush and belt.
2. Description of the Related Art
Vacuum cleaners with a rotational agitation brush are known. Typically, brush drive is accomplished by a drive belt linking an electric drive motor to the agitation brush. A common problem known in the rotational driving of an agitation brush is the accumulation of elongate particles such as hair, thread and carpet fibers about the rotational axis of the agitation brush and about the linkage mechanism connecting the drive belt to the electric motor and the agitation brush. Prior attempts have been made to inhibit and reduce the accumulation of debris around the brush and linkage mechanism are also known. One such device is disclosed in U.S. Pat. No. 2,671,923 issued to La Briere on Mar. 16, 1954. In La Briere, a suction cleaner thread guard is mounted adjacent a shaft, the shaft driving a suction fan of the cleaner and a belt for driving an agitation brush. The thread guard is planar and aligned adjacent to the shaft to encourage axial air flow into the fan, and positioned proximate the shaft to prevent threads from wrapping around shaft as the suction air flows axially into the fan.
U.S. Pat. No. 6,170,119 issued to Conrad et al. on Jan. 9, 2001, discloses a method and apparatus for reducing the size of elongate particulate matter in a vacuum cleaner head. A cutting member installed in a fixed position in the main turbine housing cooperates with the blades of the main turbine to reduce the size of particulate matter as it travels through the housing.
U.S. Pat. No. 4,445,878 to Linke et al. on May 1, 1984 discloses a chain stripper device for mining machines incorporating an arcuate blade that extends into a groove of the chain wheel in order to separate the chain from the wheel as the wheel rotates.
U.S. Pat. No. 936,887 issued to Healey on Oct. 12, 1909 discloses a belt cleaner comprising a section of belting held in a bracket so that it presses against a working surface of an operating belt to clean dirt and other foreign matter from the belt.
U.S. Pat. No. 2,560,307 issued to Slemmons on Jul. 10, 1951 discloses a band and pulley structure including a scraper element for removing foreign material from the groove of a pulley such as used in a track-type vehicle.